Downtown Chicago and O’hare are the state’s two largest employment centers.

The governor believes a “trains-to-planes” service would attract new employers and riders. Amtrak is expected to complete the study this summer, the Tribune reported.

But before any plan goes ahead, there are numerous financial and logistical questions that would have to be answered, including the route such a line might take and how it would be funded.

Calls for nonstop passenger service between downtown and O’Hare go back several years. Most notorious was the planned CTA superstation under Block 37, which sits mothballed to this day.

In the original plans for the Block 37, which now includes a mall and the building that houses CBS 2 and Morningstar, there were also plans for the CTA superstation. But it turned out to be much more expensive than planned.

When CBS 2’s Mike Parker visited in 2009, the superstation amounted to a shell 60 feet below ground level, with a bed for railroad tracks and something that appeared to be a passenger station platform. The grand, dazzling underground palace of transportation that had been envisioned had turned to gray dust.

When the project was abandoned in 2008 for an indefinite period, an estimated $250 million had been spent on it. Of that, an estimated $100 million came from cost overruns. Another $50 million was for mothball costs.

Later in 2009, the Washington Street Red Line station, which was originally closed for the construction of the planned Superstation, was taken off CTA maps, the blog Chicago Carless pointed out. But the Chicago Pedway system maintained the connection between the State/Lake Red Line and Washington Blue Line stations, via the Block 37 mall.

Last year, Mayor Richard M. Daley suggested a high-sped maglev train to O’Hare after riding a similar train in Shanghai, according to published reports.